Carton stitching machine

ABSTRACT

An improved and simplified carton stitching machine of the class used for stitching a stitch flap at one end of a paperboard carton blank to an end panel at the other end of the blank to form a tubulated carton structure. The blank is fed through the machine by powered feed rolls which are initially driven at high constant speed to advance the carton to the stitching station, then driven intermittently to feed the blank with a stepwise motion through the station during which the carton is stitched by driving of staples at intervals through the stitch flap and panel, and finally driven at high constant speed to eject the stitched carton structure from the machine. The inventive improvements reside in novel means for operating certain machine clutches and a latch member to effect shifting of the machine between its continuous feed and step feed modes and in a novel electrical counting system for counting the stitches made by the machine during each stitching cycle.

United States Patent 1 Crittenden June 19, 1973 CARTON STITCHING MACHINE [76] Inventor: Odell D. Crittenden, 18432 Drayonera Drive, Rowland, Calif. 91745 [22] Filed: Mar. 2, 1971 {21] Appl. No.: 120,116

[52] U.S. Cl 227/3, 227/7, 227/102 [51] Int. Cl B27f 7/22 [58] Field of Search 227/2, 3, 5, 6, 7,

Primary Examiner-Granville Y. Custer, Jr.- Att0rney-Boniard I. Brown [57] ABSTRACT An improved and simplified carton stitching machine of the class used for stitching a stitch flap at one end of a paperboard carton blank to an end panel at the other end of the blank to form a tubulated carton structure. The blank is fed through the machine by powered feed rolls which are initially driven at high constant speed to advance the carton to the stitching station, then driven intermittently to feed the blank with a stepwise motion through the station during which the carton is stitched by driving of staples at intervals through the stitch flap and panel, and finally driven at high constant speed to eject the stitched carton structure from the machine. The inventive improvements reside in novel means for operating certain machine clutches and a latch member to effect shifting of the machine between its continuous feed and step feed modes and in a novel electrical counting system for counting the stitches made by the machine during each stitching cycle.

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' m VEN TOR 0051.1. .0. CR TTEMDEN A 'ITORNE Y CARTON STITCHING MACHINE BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates generally to the art of paperboard carton fabrication and more particularly to improvements in carton stitching machines of the class disclosed in US. Pat. Nos. 2,305,419 and 2,908,011.

2. Discussion of the Prior Art Carton stitching machines of the class to which this invention pertains are designed for use with elongate paperboard carton blanks having three parallel, trans verse fold lines defining two end panels and two intermediate panels. Along the longitudinal edges of the panels are hinged flaps. At one end edge of one end panel is a hinged stitch flap. Each blank is fed through the stitching machine in a folded configuration wherein the stitch flap overlaps the marginal end edge portion of the distal end panel. The machine operates to stitch the stitch flap to the end panel by cutting off and forming into staples lengths of wire from a reel of wire and driving the staples at intervals through the flap and panel. The blank, when thus stitched, has a tubulated configuration and forms a tubular carton structure whose edge flaps are subsequently sealed to form a completed carton structure.

To this end, the machine has a frame mounting the wire stitching mechanism and a pair of feed rolls for feeding each blank through the machine. These feed rolls are driven from a motor on the frame through continuous high speed and step feed drives including continuous feed and step feed clutches. During each operating cycle of the machine, the clutches are initially positioned to place the machine in a continuous high speed feed mode, wherein the feed rolls are driven through the continuous feed drive to feed a blank through the machine to the stitching station at a relatively high constant speed. Upon arrival at the stitching mechanism, the leading edge of the blank engages a gage or gate which retracts to initiate the operation of the stitching mechanism and driving of the feed rolls through the step feed drive.

This action places the machine in its step feed mode and causes the blank to be fed past the stitching mechanism with a stepwise motion. Such motion is synchronized with the operation of the stitching mechanism in a manner which causes wire staples to be driven through the blank at intervals to stitch the stitch flap to the end panel, as explained above.

Also embodied in the machine is a stitch counter which counts the stitches made by the machine, i.e., the number of staples driven by the machine. At a preselected stitch count, the counter effects return of the machine to its continuous feed mode. This action causes high speed ejection of the stitched carton structure and conditions the machine for its next operating cycle.

In the existing stitching machines, the constant speed and step feed clutches and certain other machine parts which shift position during actuation of the machines from one mode to the other are controlled and operated by a relatively complex and costly electromechanical system of solenoids, switches, and levers. These machines also utilize relatively complex and costly devices for controlling the number of stitches made by the machines. The machine disclosed in US. Pat. No. 2,305,419, for example, employs a mechanical stitch counter of relatively complicated design which effects termination of the stitching operation and return of the machine to its continuous feed mode at a preset stitch count. The machine disclosed in US. Pat. No. 2,908,01 l, on the other hand, embodies a sophisticated mechanical feeler gage arrangement for controlling the stitching mechanism and returning the machine to its constant speed feed mode at the conclusion of the stitching operation.

SUMMARY OF THE INVENTION The present invention provides an improved carton stitching machine of the class described having an im' proved and simplified operating means for the continuous and step feed clutches and other mode shifting machine elements and an electrical counter for counting the stitches during each carton stitching cycle. The improved operating means comprises fluid pressure actuator means, preferably a single air cylinder, controlled by a solenoid valve which is actuated in response to movement of each carton through the machine. This actuator means normally retains the continuous feed clutch engaged and the step feed clutch disengaged to place the machine in its continuous feed mode. In this mode, the feed rolls are driven at relatively high constant speed to effect feeding of each carton blank through the machine at a relatively high constant speed.

Upon engagement of each incoming blank with the retractable gage or gate of the machine, a switch is actuated to reset to zero the electrical stitch counter and effect operation of the solenoid valve to a position wherein the fluid actuator means are pressurized to disengage the continuous feed clutch and engage the step feed clutch. This places the machine in its step feed mode. The feed rolls are then driven intermittently to effect stepwise motion of the blank past the stitching mechanism and the latter is powered to effect stitching of the blank. The electrical counter counts the number of stitches.

At a preset stitch count, the electrical counter operates the fluid actuator means to reengage the continuous feed clutch and disengage the step feed clutch and restore the machine to its continuous feed mode. The stitched carton structure is thereby ejected at high speed from the machine.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational view of the power input end of a carton stitching machine according to the invention;

FIG. 2 is'a view taken on line 2-2 in FIG. ll;

FIG. 3 is a view taken on line 3-3 in FIG. 2;

FIG. 4' is a section taken on line 4-4 in FIG. 2;

FIG. 5 is an enlarged section. through a step feed clutch of the machine;

FIG. 6 is an enlarged detail of a one-way clutch of the machine;

FIG. 7 is an enlarged section through a continuous feed clutch of the machine;

FIGS. 8 and 9 are diagrammatic illustrations of the feed roll drive train of the machine; and

FIG. 10 is a diagram of an electrohydraulic system embodied in the machine.

DESCRIPTION OF THE PREFERRED EMBODIMENT The drawings illustrate a carton stitching machine including a basic stitching machine structure 12 and improvements 14 according to the present invention. The basic machine structure 12 is essentially identical to that of the machine disclosed in U.S. Pat. No. 2,305,419. Accordingly, this basic machine structure has been illustrated in fragmentary fashion and will be described only in such detail as is required for a full and complete understanding of the invention.

With the foregoing in mind, the basic machine structure 12 comprises a frame 16 with an upstanding pedestal l8 mounting a motor 20. Rotatably supported on the frame below the motor is a drive shaft 22 for the carton stitching mechanism (not shown) of the machine. This stitching mechanism is located at a stitching station S. Rotatable on the drive shaft is a flywheel 24 which is driven continuously by the motor through a belt drive 26. A clutch 28 adjacent the flywheel has a floating clutch member 30 slidably keyed on the drive shaft for left-hand movement in FIGS. 1 and 9 to couple the shaft to the flywheel for rotation by the flywheel and right-hand movement to couple the shaft to the frame 16 for braking the shaft against rotation. Shaft 22, when driven, drives the stitching mechanism in the manner explained in U.S. Pat. No. 2.305,419. Clutch 28 is hereafter referred to in places as a step feed clutch and is shown in enlarged detail in FIG. 5.

Rotatable on the frame 16 below and to the right of the drive shaft 22 in FIG. 2 is a countershaft or continuous feed shaft 32 parallel to the drive shaft. Shaft 32 is coupled to the flywheel 24 by chain drive 34 and a clutch 36. Clutch 36 has a floating clutch member 38 slidably keyed on the countershaft for right-hand movement in FIG. 9 to connect the shaft to the flywheel for rotation by the flywheel and left-hand movement to disconnect the shaft from the flywheel such that the shaft remains stationary while the flywheel continues to turn. Clutch 36 is hereafter referred to in places as a continuous feed clutch and is shown in enlarged detail in FIG. 7.

At the right end of the frame 16 in FIGS. 1 and 8 are a control shaft 40 and a step feed shaft 42 adjacent the right end of and parallel to the drive shaft 22. As viewed in FIG. 2, the control shaft 40 is located below and to the left of the drive shaft, and the step feed shaft is located directly below the control shaft. Fixed on the right end of the drive shaft 22 is an eccentric (not shown) which actuates'a pitman 44, the upper righthand end of which in FIG. 2 is rotatable on the eccentric. The lower left end of the pitman is pivotally attached at 46 to one arm 48 of a bell crank 50 rockably mounted on the control shaft 40. The other arm 52 of man imparts an oscillating motion to the bell crank which, in turn, oscillates the one-way clutch 58 through the link 54 to drive the step feed shaft 42 with an intermittent unidirectional rotation. The slot in the clutch arm 56 permits adjustment along the arm of its attachment to the link 54 to vary the angle of rotation of the step feed shaft during each intermittent driving stroke of the clutch.

' Referring to FIGS. 8 and 9, the stitching machine has upper and lower feed rolls 68 and 70 mounted on parallel horizontal shafts 72 and 74 on the machine frame 16. The upper roll shaft 72 is drivably connected to the continuous feed shaft 32 by a sprocket chain drive 75. The lower roll shaft 74 is drivably connected to the step feed shaft 42 through an intermediate universal shaft 76 and to the upper roll shaft 72 through gearing 78 and a universal shaft 79. As explained in the earlier mentioned U.S. Pat. No. 2,305,419, the feed rolls 68, 70 are located adjacent the stitching mechanism (not shown) for feeding each carton blank past the mechamsm.

The drive chain 34, continuous feed clutch 36 and shaft 32, and the chain drive constitute a continuous feed drive or transmission 80 between the motor driven flywheel 24 and the feed rolls 68, 70. The step feed clutch 28, pitman 44, bell crank 50, link 54, one-way clutch 58, and step feed shaft 42 constitute a step feed drive or transmission 82 between the flywheel and feed rolls.

The stitching machine has two operating modes, a continuous feed mode and a step feed stitching mode. In the continuous feed mode, the continuous feed clutch 36 is engaged, the step feed clutch 28 is engaged to the frame 16 to brake shaft 22, and the feed rolls 68, 70 are driven in high speed continuous rotation through the continuous feed transmission 80. In the stitching mode, the continuous feed clutch 36 is disengaged and the step feed clutch 28 is engaged to the shaft 22. In this mode, the stitching mechanism is driven through the drive shaft 22, and the feed rolls are 7 driven in intermittent rotation through the step feed the bell crank 50 is pivotally attached at 53 to one end of a link 54. The opposite end of this link is pivotally attached to the longitudinally slotted arm 56 of a oneway drive clutch 58 on the step feed shaft 42. Referring to FIG. 6, clutch 58 has a housing 62 containing the one-way drive mechanism (not shown) of the clutch and a projecting sleeve 64 on the housing. Clutch arm 56 has a collar 66 press fitted on the sleeve.

During operation of the machine, rotation of the drive shaft 22 imparts a reciprocating motion to the pitman 44 by virtue of rotation of the shaft eccentric relative to the pitman. This reciprocating motion of the pittransmission 82. As explained in U.S. Pat. No. 2,305,419, the carton blanks are then fed with a stepwise motion past the stitching mechanism which operates to drive wire staples through the overlapping stitch flap and end panel of each blank, thus to stitch the blank into a tubulated configuration.

The stitching machine structure described to this point is conventional and essentially identical to that disclosed in U.S. Pat. No. 2,305,419. As noted earlier, this existing machine embodies a relatively complex system of levers, solenoids, and switches for operating the machine clutches 28, 36 and certain other machine elements, including a latch member 84 pivoted on the frame 16 and a lever 86 rotatable on the continuous feed shaft 22, to shift the machine between its continuous feed mode and its step feed stitching mode. In this regard, it will be understood from the patent that at the outset of each stitching cycle, the lever 86 is rocked downwardly or counterclockwise in FIG. 2 from its illustrated normal position to a lower position by a cam on the shaft 22, and the latch member 84 is rotated clockwise from its normal position of the figure to latch the lever in its lower position. This locks the machine in its step feed stitching mode. As noted earlier, the existing machine is also equipped with a relatively complex stitch counter which counts the number of stitches made in each carton, i.e., the number of staples applied to the carton, and terminates the stitching operation at a preset stitch count. At the conclusion of the stitching mode, the latch member is returned to its normal position to release the lever for return to its normal position and thereby restore the machine to its continuous feed mode.

Briefly reviewing the operation of the machine to this point, the machine is normally in its continuous feed mode. In this mode, each carton blank delivered to the machine feed rolls 68, 70 is fed at constant high speed to the stitching station S where the leading edge of the blank engages a retractable gage or gate (not shown). This causes the gate to retract and operate the machine to its step feed stitching mode. At the conclusion of the stitching cycle, the machine is restored to its continuous feed mode, and the stitched carton is fed at high speed from the machine.

The present improvements 14 replace the complex operating means or mode shifting means and the stitch counter of the existing machine and thereby simplify the machine and reduce its cost. To this end, the improvements comprise operating means 88 for operating the machine between its modes, and electrical stitch counting means 90. Operating means 88 comprises fluid actuator means including a pair of vertical bearings 92, 94 on the machine frame 16. Rotatable in the bearing 92 is a shaft 96. An arm 98 is fixed to and extends laterally from the lower end of the shaft. A pneumatic or hydraulic cylinder 100 is pivotally connected between the outer end of the arm and the frame 16 for rotating the arm and thereby the shaft 96. Fixed to the upper end of the shaft 96 is an arm 102 terminating in a fork 104 which straddles and is pivotally attached to the floating clutch member 30 of the step feed clutch 28. From this it will be understood that the cylinder 100 is operable to shift the clutch member between its drive position wherein it couples the flywheel 24 to the shaft 22 and its brake position wherein it couples the shaft to the frame.

Rotatable in the bearing 94 is a shaft 106 to the lower end of which is fixed a transverse arm 108. The outer end of arm 108 is pivotally attached to the arm 98 by an adjustable link 110. Arm 108 and shaft 106 thus rotate in unison with arm 98 and shaft 96. Attached to the upper end of shaft 106 is an arm 112 terminating in a fork 114 which straddles and is pivotally attached to the floating clutch member 38 of the continuous feed clutch 36. Accordingly, the cylinder 100 is also operable to shift the clutch member 38 between its engaged or drive and disengaged positions. The actuator means 88 is so arranged that extension of the cylinder 100 moves the step feed clutch member 30 to braking position and the continuous feed clutch member 38 to drive position to place the machine in its continuous feed mode. Contraction of the cylinder moves the step feed clutch member to drive position and the continuous feed clutch member38 to disengaged position to place the machine in its step feed mode.

Also fixed to the shaft 106 for the continuous feed clutch shift arm 112 is an arm 116 which engages an adjustment screw 118 threaded in the lower end of the latch member 84. Arm 116 and screw 118 are so adjusted that counterclockwise rotation of the arm with the shaft in FIG. 3 to engage the continuous feed clutch 36 effects return of the latch member to its normal unlatching position. As noted above, this releases the lever 86 for return to its normal position to terminate the stitching operation and restore the machine to its continuous feed mode. Clockwise rotation of the arm 116 with the shaft 106 to disengage the clutch 36 releases the latch member for rotation to its latching position at the outset of the stitching operation, as explained above and in the referenced patent.

Turning to FIG. 10, the operating fluid, in this instance air, to the actuator cylinder is controlled by a solenoid valve 120. The valve has an inlet 122 connected to a source of high pressure air and outlets 124, 126 connected to the cylinder ends. Valve is electrically connected to an energizing circuit 128 including an electrical power source 130, an electrical pulse counting and switching device 132, hereafter referred to simply as a counter, a counting switch 134, and a reset switch 136. Referring to FIGS. 1 and 2, the counting switch 134 is mounted on the machine frame 16 below the right end of the drive shaft 22 in FIG. 1 and is actuated by a cam 138 on the shaft in such a way that the .switch is closed once to produce a single electrical pulse during each shaft revolution. The reset switch 136 is operated by the retractable gage or gate (not shown) of the machine in such a way that retraction of the gate by each incoming carton blank in the manner explained in US. Pat. No. 2,305,419 closes the switch.

The circuit 128 is so arranged that closure of the reset switch 136 by each incoming blank resets the counter 132 to zero. The counter, when thus reset, actuates the solenoid valve 120 to release the latch member 84 for rotation to latching position and shift the step feed clutch 28 to drive position and the continuous feed clutch 36 to disengaged position, thereby placing the machine in its step feed stitching mode. In this mode, the counting switch 134 produces one pulse for each revolution of the drive shaft 22. The drive shaft, in turn, drives the stitching mechanism in such a way that one stitch is made in the carton blank currently in the machine, i.e., one staple is driven into the blank, during each shaft revolution. Accordingly, the total number of pulses produced represents the total number of stitches made. The counter 132 counts these pulses and at a preselected stitch count preset into the counter operates the solenoid valve 120 to restore the machine to its continuous feed mode by returning the step feed clutch 28 to its braking position, the continuous feed clutch 36 to its engaged or drive position, and the latch member 84 to its normal or unlatched position.

It will now be understood that prior to entrance of a carton blank into the stitching machine, the step feed clutch 28 is in braking position, the continuous feed clutch 36 is in engaged or drive position, and the latch member 84 occupies its normal unlatching position of FIG. 2. When a carton is fed to the machine feed rolls 68, 70, the latter grip and feed the blank at relatively high constant speed to the stitching station S. Upon arrival at this station, the blank actuates the reset switch 136 to reset the counter 132 to zero and effect operation of the machine to its step feed stitching mode. The blank is thereby fed through the stitching station with a stepwise motion and is stitched at intervals by the stitching mechanism to form a twbulated carton structure. The counter 132 counts the stitches made. At the preset stitch count, the counter restores the machine to its continuous feed mode. The carton structure is then fed at high speed from the machine, and the latter is conditioned to receive the next carton blank.

What is claimed as new in support of Letters Patent 1. In a carton stitching machine having feed rolls for feeding carton blanks to be stitched through the machine along a prescribed path of motion, a carton stitching station along said path, drive means for said feed rolls including a continuous feed clutch having a clutch member which is movable to a drive position to effect constant speed rotation of said feed rolls and a step feed clutch having a clutch member which is movable to a drive position to effect intermittent rotation of said feed rolls, and said clutches being operable to shift said machine between a continuous feed mode wherein said feed rolls rotate at constant speed to feed a carton blank in continuous fashion to and vfrom said stitching station and a step feed stitching mode wherein said feed rolls undergo intermittent rotation to feed a carton blank in stepwise fashion through said stitching station to effect stitching of said blank, the improvements comprising:

fluid actuator means operatively connected to said clutch members for moving said clutch members to drive positions alternately, means including a solenoid valve for supplying working fluid to said actuator means to effect movement of said continuous feed clutch member to drive position in response to operation of said valve to a first position and movement of said step feed clutch member to drive position in response to operation of said valve to a second position, said actuator means comprising a pair of shafts rotatably supported on said frame, an arm rigid on one shaft and operatively connected to said continuous feed clutch member for moving said latter clutch member to and from drive position upon rotation of said one shaft in one direction and then the other, an arm rigid on the other shaft and operatively connected to said step feed clutch member for moving the latter clutch member to and from drive position upon rotation of said other shaft in one direction and then the other, and fluid pressure operated means controlled by said valve for rotating said shafts to move said continuous feed clutch member to drive position upon operation of said valve to said first position and said step feed clutch member to drive position upon operation of said valve to said second position, and control circuit means for said valve including a switch which is actuated by each carton blank driving at said stitching station for effecting operation of said valve to said second position to place said machine in said step feed mode, and stitch counting means for counting the stitches produced during said step feed mode and effecting operation of said valve to said first position to place said machine in said continuous feed mode at a preselected stitch count. 2. The improvements according to claim 1 wherein: said fluid pressure operating means comprises a common fluid pressure actuator such as a pneumatic cylinder for rotating both shafts in unison. 3. The improvements according to claim 2 wherein: said machine includes bearings rotatably supporting said shafts in parallel side by side relation, said actuator means include additional arms fixed to said shafts,

said fluid pressure actuator is connected to one additional shaft arm, and

means connecting said additional shaft arms,

whereby said actuator is operable to rotate both shafts.

4. In a carton stitching machine having feed rolls for feeding carton blanks to be stitched through the machine along a prescribed path of motion, a carton stitching station along said path, drive means for said feed rolls including a continuous feed clutch having a clutch member which is movable to a drive position to effect constant speed rotation of said feed rolls and a step feed clutch having a clutch member which is movable to a drive position to effect intermittent rotation of said feed rolls, and said clutches being operable to shift said machine between a continuous feed mode wherein said feed rolls rotate at constant speed to feed a carton blank in continuous fashion to and from said stitching station and a step feed stitching mode wherein said feed rolls undergo intermittent rotation to feed a carton blank in stepwise fashion through said stitching station to effect stitching of said blank, the improvements. comprising:

fluid actuator means operatively connected to said clutch members for moving said clutch members to drive positions alternately,

means including a solenoid valve for supplying working fluid to said actuator means,

said actuator means comprises a pair of shafts rotatably supported on said frame, an arm rigid on one shaft and operatively connected to said continuous feed clutch member for moving said latter clutch member to and from drive position upon rotation of said one shaft in one direction and then the other, an arm rigid on the other shaft and operatively connected to said step feed clutch member for moving the latter clutch member to and from drive position upon rotation of said other shaft in one direction and then the other, and fluid pressure operated means controlled by said valve for rotating said shafts to move said continuous feed clutch member to drive position upon operation of said valve to said first position and said step feed clutch member to drive position upon operation of said valve to said second position,

operation of said machine in said step feed mode constituting a stitching cycle which commences upon movement of said step feed clutch member to drive position and ceases upon movement of said continuous feed clutch member to drive position, a latch member which is rotatable from a normal unlatching position to a latching position at the outset of said stitching cycle to lock said machine in said step feed mode,

means for returning said latch member to normal position concurrently with movement of said step feed clutch member from drive position and movement of said continuous feed clutch member to drive position at the conclusion of said stitching cycle comprising an arm fixed on one shaft and engaging said latch member in a manner such that rotation of the latter arm with the latter shaft at the conclusion of said stitching cycle rotates said latch member to normal position and rotation of the latter arm with the latter shaft at the start of said cycle releases said latch member for rotation to latching position, and

control circuit means for said valve including a switch which is actuated by each carton blank driving at said stitching station for effecting operation of said valve to said second position to place said machine in said step feed mode, and stitch counting means for counting the stitches produced during said step feed mode and effecting operation of said valve to said first position to place said machine in said continuous feed mode at a preselected stitch count.

5. The improvements according to claim 4 wherein:

said fluid pressure operating means comprises a common fluid pressure actuator such as a pneumatic cylinder for rotating both shafts in unison.

6. The improvements according to claim 5 wherein:

said machine includes bearings rotatably supporting said shafts in parallel side by side relation,

said actuator means include additional arms fixed to said shafts,

said fluid pressure actuator is connected to one additional shaft arm, and

means connecting said additional shaft arms, whereby said actuator is operable to rotate both shafts.

7. The improvements according to claim 6 wherein:

said stitch counting means comprises means for generating electrical pulses whose number represents the number of stitches made by said machine in said step feed mode, and an electrical counter for counting said pulses and effecting operation of said valve to said first position at said preselected stitch count.

8. The improvements according to claim 7 wherein:

said machine includes a stitching mechanism at said stitching station and a drive shaft for said stitching mechanism which is coupled to said step feed clutch in a manner such that movement of said step feed clutch member to drive position causes rotation of said drive shaft to drive said mechanism, and

said pulse generating means comprises a counting switch and a cam on said drive shaft for opening and closing said switch during rotation of said drive shaft.

9. The improvements according to claim 8 wherein:

said first mentioned switch is connected to said counter to reset the latter to zero upon actuation of the latter switch by each carton blank arriving at said stitching station, and said counter is connected to said valve to operate said valve to said first position in response to resetting of said counter.

10. The improvements according to claim 9 wherein:

operation of said machine in said step feed mode constitutes a stitching cycle which commences upon movement of said step feed clutch member to drive position and ceases upon movement of said continuous feed clutch member to drive position,

said machine includes a latch member which is rotatable from a normal unlatching position to a latching position at the outset of said stitching cycle to lock said machine in said step feed mode, and

said actuator means includes means for returning said latch member to normal position concurrently with movement of said step feed clutch member from drive position and movement of said continuous feed clutch member to drive position at the conclusion of said stitching cycle.

11. In a carton stitching machine having feed rolls for feeding carton blanks to be stitched through the machine along a prescribed path of motion, a carton stitching station along said path, drive means for said feed rolls including a continuous feed clutch having a clutch member which is movable to a drive position to effect constant speed rotation of said feed rolls and a step feed clutch having a clutch member which is movable to a drive position to effect intermittent rotation of said feed rolls, a stitching mechanism at said stitching station, and a drive shaft for said mechanism driven through said step feed clutch in a manner such that movement of said step feed clutch member to drive po sition effects rotation of said drive shaft to drive said mechanism, and said clutches being operable to shift said machine between a continuous feed mode wherein said feed rolls rotate at constant speed to feed a carton blank in continuous fashion to and from said station and a step feed stitching mode wherein said feed rolls undergo intermittent rotation to feed a carton blank in stepwise fashion through said station and said stitching mechanism is driven by said drive shaft to effect stitching of said blank, the improvement comprising:

operating means for effecting movement of said step feed clutch member to drive position to place said machine in said step feed mode in response to arrival of each carton blank at said station and movement of said continuous feed clutch member to drive position to place said machine in said continuous feed mode in response to a preselected stitch count, operating means comprising means for generating an electrical pulse in response to each stitch made by said stitching mechanism in said step feed mode, an electrical pulse counter for counting said pulses, means electrically connected to said counter and actuated by each carton blank arriving at said station for electrically re-setting said counter to zero, and means electrically controlled by said counter for operating said step feed clutch member to drive position and said continuous feed clutch member from said drive position upon resetting of the counter to zero and operating said continuous feed clutch member to drive position and said step feed clutch member from drive position in response to an accumulated pulse count in,

said counter equal to said pre-selected step count. 

1. In a carton stitching machine having feed rolls for feeding carton blanks to be stitched through the machine along a prescribed path of motion, a carton stitching station along said path, drive means for said feed rolls including a continuous feed clutch having a clutch member which is movable to a drive position to effect constant speed rotation of said feed rolls and a step feed clutch having a clutch member which is movable to a drive position to effect intermittent rotation of said feed rolls, and said clutches being operable to shift said machine between a continuous feed mode wherein said feed rolls rotate at constant speed to feed a carton blank in continuous fashion to and from said stitching station and a step feed stitching mode wherein said feed rolls undergo intermittent rotation to feed a carton blank in stepwise fashion through said stitching station to effect stitching of said blank, the improvements comprising: fluid actuator means operatively connected to said clutch members for moving said clutch members to drive positions alternately, means including a solenoid valve for supplying working fluid to said actuator means to effect movement of said continuous feed clutch member to drive position in response to operation of said valve to a first position and movement of said step feed clutch member to drive position in response to operation of said valve to a second position, said actuator means comprising a pair of shafts rotatably supported on said frame, an arm rigid on one shaft and operatively connected to said continuous feed clutch member for moving said latter clutch member to and from drive position upon rotation of said one shaft in one direction and then the other, an arm rigid on the other shaft and operatively connected to said step feed clutch member for moving the latter clutch member to and from drive position upon rotation of said other shaft in one diRection and then the other, and fluid pressure operated means controlled by said valve for rotating said shafts to move said continuous feed clutch member to drive position upon operation of said valve to said first position and said step feed clutch member to drive position upon operation of said valve to said second position, and control circuit means for said valve including a switch which is actuated by each carton blank driving at said stitching station for effecting operation of said valve to said second position to place said machine in said step feed mode, and stitch counting means for counting the stitches produced during said step feed mode and effecting operation of said valve to said first position to place said machine in said continuous feed mode at a preselected stitch count.
 2. The improvements according to claim 1 wherein: said fluid pressure operating means comprises a common fluid pressure actuator such as a pneumatic cylinder for rotating both shafts in unison.
 3. The improvements according to claim 2 wherein: said machine includes bearings rotatably supporting said shafts in parallel side by side relation, said actuator means include additional arms fixed to said shafts, said fluid pressure actuator is connected to one additional shaft arm, and means connecting said additional shaft arms, whereby said actuator is operable to rotate both shafts.
 4. In a carton stitching machine having feed rolls for feeding carton blanks to be stitched through the machine along a prescribed path of motion, a carton stitching station along said path, drive means for said feed rolls including a continuous feed clutch having a clutch member which is movable to a drive position to effect constant speed rotation of said feed rolls and a step feed clutch having a clutch member which is movable to a drive position to effect intermittent rotation of said feed rolls, and said clutches being operable to shift said machine between a continuous feed mode wherein said feed rolls rotate at constant speed to feed a carton blank in continuous fashion to and from said stitching station and a step feed stitching mode wherein said feed rolls undergo intermittent rotation to feed a carton blank in stepwise fashion through said stitching station to effect stitching of said blank, the improvements comprising: fluid actuator means operatively connected to said clutch members for moving said clutch members to drive positions alternately, means including a solenoid valve for supplying working fluid to said actuator means, said actuator means comprises a pair of shafts rotatably supported on said frame, an arm rigid on one shaft and operatively connected to said continuous feed clutch member for moving said latter clutch member to and from drive position upon rotation of said one shaft in one direction and then the other, an arm rigid on the other shaft and operatively connected to said step feed clutch member for moving the latter clutch member to and from drive position upon rotation of said other shaft in one direction and then the other, and fluid pressure operated means controlled by said valve for rotating said shafts to move said continuous feed clutch member to drive position upon operation of said valve to said first position and said step feed clutch member to drive position upon operation of said valve to said second position, operation of said machine in said step feed mode constituting a stitching cycle which commences upon movement of said step feed clutch member to drive position and ceases upon movement of said continuous feed clutch member to drive position, a latch member which is rotatable from a normal unlatching position to a latching position at the outset of said stitching cycle to lock said machine in said step feed mode, means for returning said latch member to normal position concurrently with movement of said step feed clutch member from drive position and movement of said continuous feed clutch Member to drive position at the conclusion of said stitching cycle comprising an arm fixed on one shaft and engaging said latch member in a manner such that rotation of the latter arm with the latter shaft at the conclusion of said stitching cycle rotates said latch member to normal position and rotation of the latter arm with the latter shaft at the start of said cycle releases said latch member for rotation to latching position, and control circuit means for said valve including a switch which is actuated by each carton blank driving at said stitching station for effecting operation of said valve to said second position to place said machine in said step feed mode, and stitch counting means for counting the stitches produced during said step feed mode and effecting operation of said valve to said first position to place said machine in said continuous feed mode at a preselected stitch count.
 5. The improvements according to claim 4 wherein: said fluid pressure operating means comprises a common fluid pressure actuator such as a pneumatic cylinder for rotating both shafts in unison.
 6. The improvements according to claim 5 wherein: said machine includes bearings rotatably supporting said shafts in parallel side by side relation, said actuator means include additional arms fixed to said shafts, said fluid pressure actuator is connected to one additional shaft arm, and means connecting said additional shaft arms, whereby said actuator is operable to rotate both shafts.
 7. The improvements according to claim 6 wherein: said stitch counting means comprises means for generating electrical pulses whose number represents the number of stitches made by said machine in said step feed mode, and an electrical counter for counting said pulses and effecting operation of said valve to said first position at said preselected stitch count.
 8. The improvements according to claim 7 wherein: said machine includes a stitching mechanism at said stitching station and a drive shaft for said stitching mechanism which is coupled to said step feed clutch in a manner such that movement of said step feed clutch member to drive position causes rotation of said drive shaft to drive said mechanism, and said pulse generating means comprises a counting switch and a cam on said drive shaft for opening and closing said switch during rotation of said drive shaft.
 9. The improvements according to claim 8 wherein: said first mentioned switch is connected to said counter to reset the latter to zero upon actuation of the latter switch by each carton blank arriving at said stitching station, and said counter is connected to said valve to operate said valve to said first position in response to resetting of said counter.
 10. The improvements according to claim 9 wherein: operation of said machine in said step feed mode constitutes a stitching cycle which commences upon movement of said step feed clutch member to drive position and ceases upon movement of said continuous feed clutch member to drive position, said machine includes a latch member which is rotatable from a normal unlatching position to a latching position at the outset of said stitching cycle to lock said machine in said step feed mode, and said actuator means includes means for returning said latch member to normal position concurrently with movement of said step feed clutch member from drive position and movement of said continuous feed clutch member to drive position at the conclusion of said stitching cycle.
 11. In a carton stitching machine having feed rolls for feeding carton blanks to be stitched through the machine along a prescribed path of motion, a carton stitching station along said path, drive means for said feed rolls including a continuous feed clutch having a clutch member which is movable to a drive position to effect constant speed rotation of said feed rolls and a step feed clutch having a clutch member which is movable to a drive position to effect intermittent rotation of said feed rolls, a stitching mechanism at said stitching station, and a drive shaft for said mechanism driven through said step feed clutch in a manner such that movement of said step feed clutch member to drive position effects rotation of said drive shaft to drive said mechanism, and said clutches being operable to shift said machine between a continuous feed mode wherein said feed rolls rotate at constant speed to feed a carton blank in continuous fashion to and from said station and a step feed stitching mode wherein said feed rolls undergo intermittent rotation to feed a carton blank in stepwise fashion through said station and said stitching mechanism is driven by said drive shaft to effect stitching of said blank, the improvement comprising: operating means for effecting movement of said step feed clutch member to drive position to place said machine in said step feed mode in response to arrival of each carton blank at said station and movement of said continuous feed clutch member to drive position to place said machine in said continuous feed mode in response to a preselected stitch count, operating means comprising means for generating an electrical pulse in response to each stitch made by said stitching mechanism in said step feed mode, an electrical pulse counter for counting said pulses, means electrically connected to said counter and actuated by each carton blank arriving at said station for electrically re-setting said counter to zero, and means electrically controlled by said counter for operating said step feed clutch member to drive position and said continuous feed clutch member from said drive position upon re-setting of the counter to zero and operating said continuous feed clutch member to drive position and said step feed clutch member from drive position in response to an accumulated pulse count in said counter equal to said pre-selected step count. 